Any search for the "perfect diet” may be a fool's errand.
After all, people's reactions to foods vary by their genetic profiles and health status.
That said, there's a mountain of evidence in favor of the so-called Mediterranean diet.
People who follow a Mediterranean-style diet suffer less from heart disease, cancer, and degenerative brain diseases like Parkinson's and Alzheimer's.
In reality, the "Mediterranean diet” studied by researchers should be called the "rural Greek diet” or the "Aegean islands diet”, because it reflects how people in those regions eat.
This idealized Mediterranean diet features fruits, veggies, nuts, cheese, yogurt, extra virgin olive oil, herbs, spices, sparing amounts of salt, and modest amounts of protein ... coming more from fish and poultry than from red meats.
Of course, the Mediterranean diet isn't the only healthy one in the world.
A new study confirms what many would suspect ... Japan's traditional diet protects health and extends lifespans.
Japan's "Spinning Top" diet plan
Compared with Americans, people in Japan enjoy markedly better health.
Japan has lower rates of heart disease, cancer, depression, and dementia conditions such as Alzheimer's disease.
And, compared with the U.S., Japan has higher proportions of people aged 100 years or older, with average life expectancy continuing to rise.
Some call this remarkable record of superior national health and longevity the "Japanese miracle”.
In 2000, Japan issued official diet guidelines based loosely on the traditional Japanese diet, and later released a graphic version called the Food Guide Spinning Top.
It resembles the U.S. Food Guide Pyramid, but Japan's Spinning Top suggests somewhat different proportions of various food groups.
Like the U.S. Pyramid, it emphasizes plant foods — grains, veggies, and fruits — but Japan's Spinning Top recommends smaller amounts of meat, poultry, and milk products.
Study results elevate Japan's diet
The new epidemiological study comes from Tokyo's National Centre for Global Health and Medicine.
Researchers there set out to examine the link between people's adherence to Japan's Spinning Top eating plan and their risk for death from various causes.
The scientists gathered diet and lifestyle data from 36,624 men and 42,970 women between the ages of 45 and 75.
They followed the participants for 15 years, and found that men and women who followed the food guidelines closely were 15 percent less likely to die before the end of the study.
(Note: While an epidemiological study can provide useful indications, it cannot prove a cause-effect relationship between the participants' diets and their health outcomes.)
As you might expect, people who adhered closely to the diet were less likely to die from cardiovascular disease.
However, most of the overall death-reduction benefit was linked to reduced deaths caused by cerebrovascular disease.
Like cardiovascular disease, cerebrovascular disease is characterized by build-up and oxidation of arterial plaque. It can initiate brain-damaging, stroke-inducing clots, embolisms, aneurysms, and hemorrhages, which can trigger or worsen dementia.
Surprisingly, cancer rates were not substantially lower among people who adhered most closely to the Japanese food guidelines.
Why would that be?
Japan already enjoys one of the lowest cancer rates* among developed countries (such as the U.S. and Europe), and its official diet guidelines were based on the way most Japanese eat.
*Compared with Japan, cancer rates are lower in most of Africa, the Middle East, Central America, and South America (see the global cancer map) … regions that are much less industrialized. So factors other than diet — such as exposure to industrial pollutants — may explain the relatively higher cancer risks in Japan.
Details of the Japanese study prove revealing
There were differences among people who adhered closely to Japan's official diet guidelines overall, depending on how closely they followed specific parts of the guidelines:
- High intakes of fruits and vegetables were linked to lower risk for death from any cause.
- High intakes of vegetables and fruits were linked to lower risks for death from cardiovascular disease.
- High intakes of vegetables, fish, meat, milk, and fruits were linked to a lower risk of death from any cause.
- High intakes of fish, meat, and/or fruits were linked to lower risks for death from cerebrovascular disease … and, when milk intakes were also relatively high, to lower risks for heart disease.
Some of these results are surprising.
For example, the healthiness of the Japanese diet isn't typically associated with higher intakes of meat or milk.
And Westerners tend to assume that soy foods play a large role in the relative healthiness and longevity of the Japanese people … but that was not the case in this study.
Instead of soy, higher intakes of fish, meat, fruits, and vegetables were found to reduce the risk for death from any cause.
We should also note that many of the noodle products eaten by Japanese people (such as soba and udon) feature buckwheat … a grain-like, antioxidant-rich seed far different from wheat (see A New Wave of Old Grains
What explains the Japanese miracle?
So what makes the Japanese diet especially healthful?
The official Japanese and American dietary guidelines recommend similar proportions and types of carbohydrate, fat, and protein.
But the average Japanese person eats more vegetables ... and, compared with the average American's yen for meat and poultry, seafood plays a much larger role in the Japanese diet.
In addition to ample protein, fish and shellfish abound in the omega-3 fats (DHA and EPA) linked strongly to better cardiovascular, immune, and brain health.
Importantly — compared with the average American's diet — the Japanese diet has fewer omega-6 fats (from cheap vegetable oils).
The average American's excessive intake of omega-6 fats is linked to higher risks for common cancers and major heart, brain, and immune disorders … see "Omega-3/6 Balance: Hidden Health Risk
To enable good health, limit your intake of cheap, omega-6-laden oils — corn, soy, safflower, sunflower, cottonseed — in favor of low-omega-6 choices like olive, macadamia, coconut, and "hi-oleic" sunflower oils.
And boost your intake of the most beneficial omega-3s (DHA and EPA) by eating seafood at least twice a week or taking fish-, shellfish-, or algae-oil capsules.
Clearly, there's more to the Japanese diet than its healthier balance between omega-3 and omega-6 fats.
But there's plenty of evidence that it's a major reason for the Asian nation's superior health and longevity.
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